Inhibitory effect of an intellectual task on breathing after
voluntary hyperventilation.
Chin, Kazuo, Motoharu Ohi, Motonari Fukui, Hideo Kita, Tomomasa
Tsuboi, Tetsuo Noguchi, Naoki Otsuka, Hiromichi Hirata, Michiaki
Mishima, and Kenshi Kuno.
Department of Clinical Physiology, Chest Disease Research
Institute, Kyoto University, Shogoin-Kawaharacho 53, Sakyo-Ku, Kyoto
606, Japan
APStracts 3:0189A, 1996.
We investigated the effects of an intellectual ?task on post
-hyperventilation (PHV) breathing using a video game. Eight normal
subjects were placed in a supine position. The game task by itself
led to increased ventilation compared to the controls via an increase
in the average inspiratory flow rate (VT/TI) (p<0.01) and the
respiratory frequency (p<0.001). After hypocapnic voluntary
hyperventilation (VHV), the task led to a decrease in the one minute
PHV breathing level compared to the controls following VHV (first 60
seconds of average minute ventilation (E) while watching television
following VHV: 5.54+/-2.91 L/min; while playing a video game
following VHV: 2.05+/-1.40 L/min, p<0.01). Although only one
subject showed PHV apnea for at least 10 seconds during the
control?protocol, 7 of the same 8 subjects showed PHV apnea while
performing the task. After isocapnic VHV, the task still led to a
decrease in PHV breathing compared to the controls following
isocapnic VHV. However, this decrease was smaller than in the
hypocapnic studies, and was only significant during the first 15 sec
of recovery. These results suggest that increased activity in the
higher centers of the CNS has an inhibitory effect on PHV breathing
at a time when the effects of short-term potentiation following VHV,
hypocapnia and perhaps other mechanisms would be expected to be
acting on breathing.
Received 29 November 1994; accepted in final form 2 April 1996.
APS Manuscript Number A1215-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 16 April 96